One-to-many communication service using composite broadcast/multicast flows in a wireless network

Abstract

Methods and systems for providing one-to-many communication services (e.g., push-to-talk (PTT)) using composite broadcast/multicast flows in a wireless network are disclosed. A permanent broadcast/multicast control flow is used to provide session control information (e.g., announcements for replacing the traditional paging and connection setup) and OAM messages to the subscribers of the one-to-many communication service. If a request for a communication session to a group of subscribers is initiated in the wireless network, then one or more broadcast/multicast content flows are established in the wireless network to the subscribers in the group. The broadcast/multicast content flows are used to provide signaling for the session, the audio for the session, or other media type of content for the session to the subscribers in the group.

1 . A method of using composite broadcast/multicast flows to provide a one-to-many communication service in a wireless network, the method comprising:
 establishing a broadcast/multicast control flow in the wireless network to subscribers of the one-to-many communication service;   responsive to receiving a request for a communication session in the wireless network to a group of subscribers of the one-to-many communication service, transmitting session control information for the communication session to the subscribers in the group over the broadcast/multicast control flow;   establishing at least one broadcast/multicast content flow in the wireless network to the subscribers in the group; and   transmitting content for the communication session over the at least one broadcast/multicast content flow to the subscribers in the talkgroup.   
   
   
       2 . The method of  claim 1  wherein transmitting session control information for the communication session includes:
 transmitting an announcement for the communication session over the broadcast/multicast control flow.   
   
   
       3 . The method of  claim 1  further comprising:
 identifying RNCs and sectors corresponding with the locations of the subscribers in the group; and   establishing the at least one broadcast/multicast content flow to the identified sectors.   
   
   
       4 . The method of  claim 1  wherein the broadcast/multicast control flow and the at least one broadcast/multicast content flow comprise Broadcast and Multicast Service (BCMCS) flows. 
   
   
       5 . The method of  claim 1  wherein the one-to-many communication service comprises a push-to-talk (PTT) service. 
   
   
       6 . The method of  claim 1  wherein the content for the communication session comprises at least one of audio and signaling. 
   
   
       7 . The method of  claim 1  wherein the wireless network comprises a cdma2000 (1×EV-DO) wireless network. 
   
   
       8 . A wireless network adapted to provide a one-to-many communication service using composite broadcast/multicast flows, the wireless network comprising:
 a radio network controller (RNC) adapted to communicate with subscribers of the one-to-many communication service; and   a one-to-many communication system adapted to establish a broadcast/multicast control flow through the RNC to the subscribers, receive a request for a communication session to a group of subscribers of the one-to-many communication service, transmit session control information for the communication session to the subscribers in the group over the broadcast/multicast control flow, and establish at least one broadcast/multicast content flow to the RNC;   the RNC is further adapted to establish at least one additional broadcast/multicast content flow to a sector of the RNC having subscribers in the group or establish at least one individual traffic channel to the sector having the subscribers in the group based on the number of subscribers in the sector;   the one-to-many communication system is further adapted to transmit content for the communication session over the at least one broadcast/multicast content flow to the RNC;   the RNC is further adapted to transmit the content for the communication session over the at least one additional broadcast/multicast content flow established to the sector having subscribers in the group, or over the at least one individual traffic channel to the subscribers in the group.   
   
   
       9 . The wireless network of  claim 8  wherein the RNC is further adapted to maintain a distribution table for the group to determine the number of subscribers in the sector. 
   
   
       10 . The wireless network of  claim 8  wherein the session control information includes an announcement for the communication session. 
   
   
       11 . The wireless network of  claim 8  wherein the broadcast/multicast control flow and the at least one broadcast/multicast content flow comprise Broadcast and Multicast Service (BCMCS) flows. 
   
   
       12 . The wireless network of  claim 8  wherein the one-to-many communication service comprises a push-to-talk (PTT) service. 
   
   
       13 . The wireless network of  claim 8  wherein the content for the communication session comprises at least one of audio and signaling. 
   
   
       14 . The wireless network of  claim 8  wherein the wireless network comprises a cdma2000 (1×EV-DO) wireless network. 
   
   
       15 . A method of providing an enhanced Push to Talk (PTT) service in a wireless network, the method comprising:
 establishing a Broadcast and Multicast Service (BCMCS) control flow in the wireless network to subscribers of the PTT service wherein the BCMCS control flow is adapted to provide session control information to the subscribers;   maintaining distribution tables for talkgroups of the PTT service;   receiving a PTT call request in the wireless network to a talkgroup having a plurality of the subscribers;   establishing additional BCMCS content flows in the wireless network to the subscribers in the talkgroup responsive to the PTT call wherein the additional BCMCS content flows are adapted to provide PTT content for the PTT call to the subscribers in the talkgroup;   transmitting a call announcement to the subscribers in the talkgroup over the BCMCS control flow; and   transmitting content for the PTT call over the additional BCMCS content flows to the subscribers in the talkgroup.   
   
   
       16 . The method of  claim 15  wherein receiving a PTT call request to a talkgroup in the wireless network comprises:
 receiving a BCMCS registration message to the at least one BCMCS content flow assigned to the talkgroup from an originating access terminal.   
   
   
       17 . The method of  claim 15  further comprising:
 receiving BCMCS registration messages for the BCMCS control flow from the subscribers; and   generating distribution tables for talkgroups responsive to the registration messages, wherein a distribution table of a talkgroup indicates sectors within an RNC in the wireless network having subscribers of the talkgroup.   
   
   
       18 . The method of  claim 15  wherein transmitting a call announcement to the subscribers in the talkgroup over the BCMCS control flow comprises:
 transmitting the call announcement including session related parameters and a BCMCS Broadcast Overhead Message including BCMCS content flow related parameters as a single message to the subscribers in the talkgroup over the BCMCS control flow.   
   
   
       19 . The method of  claim 15  wherein the content for the communication session comprises at least one of audio and signaling. 
   
   
       20 . The method of  claim 15  wherein the BCMCS control flow is permanently established for the PTT service, and the BCMCS content flows are dynamically established for the PTT call.